21520617737330 has 16 divisors (see below), whose sum is σ = 38738214517464. Its totient is φ = 8608002074880.

The previous prime is 21520617737321. The next prime is 21520617737387. The reversal of 21520617737330 is 3373771602512.

It can be written as a sum of positive squares in 4 ways, for example, as 16607980433521 + 4912637303809 = 4075289^2 + 2216447^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30258401 + ... + 30961460.

Almost surely, 2^{21520617737330} is an apocalyptic number.

21520617737330 is a deficient number, since it is larger than the sum of its proper divisors (17217596780134).

21520617737330 is a wasteful number, since it uses less digits than its factorization.

21520617737330 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61255021.

The product of its (nonzero) digits is 1111320, while the sum is 47.

The spelling of 21520617737330 in words is "twenty-one trillion, five hundred twenty billion, six hundred seventeen million, seven hundred thirty-seven thousand, three hundred thirty".